The Pico bears a striking resemblance to the Streamlight Nanolight, the bezel of which regularly unscrews on its own. I've had to tape it in place to keep the batteries from falling out accidentally. IMHO, those 4 teeny batteries are too "fiddly". And if the Pico's little battery holder cracks or is misplaced, the light might be DOA (unacceptable in an emergency). I much prefer a less fiddly single battery light, preferably using a lithium cell.